1. Technical Field
The present invention relates to a physical quantity sensor, a vibratory device, an electronic apparatus, and a moving object.
2. Related Art
In general, there are known a physical quantity sensor and a vibratory device as an electromechanical structure provided with a mechanically movable structure. As the physical quantity sensor, there is known, for example, a capacitive sensor, which is provided with a stationary electrode fixedly disposed on a substrate, and a movable electrode disposed so as to be opposed to the stationary electrode across a gap and to be able to be displaced in accordance with the action of a physical quantity (e.g., acceleration and an angular velocity), and detects the physical quantity based on the capacitance between the stationary electrode and the movable electrode.
Such a capacitive sensor is configured so that a relatively high capacitance is formed by forming the movable electrode and the stationary electrode to have a comb-like shape, and forming the wiring so that the stationary electrode is disposed on one side or both sides of the movable electrode so that the comb teeth of the electrodes are interleaved with each other.
In JP-A-2013-19906, there is proposed a technology for preventing deformation of the movable electrode due to an external stress by disposing stress-blocking slits between a fixation section (an anchor section) of the movable electrode and the movable electrode in a physical quantity sensor having such a structure. According to JP-A-2013-19906, since the external stress is absorbed by the slits, and thus the deformation of the movable electrode can be prevented, degradation of the detection accuracy as the sensor can be prevented.
However, in the technology of JP-A-2013-19906, there is a problem that in some cases, the external stress caused in the fixation section cannot be fully absorbed. Specifically, the problem is as follows. Even in the case in which the slits are provided as described in JP-A-2013-19906, the area (the area between the slits opposed to each other) not provided with the slits remains as an area through which the stress can be directly transmitted from the fixation section to the movable electrode, and further, the area is located in the vicinity of an extension of the displacement direction (moving direction) of a base portion (a portion supported by the fixation section and giving a shape to the comb-like electrode portion) of the movable electrode, and therefore, in some cases, the movable electrode is deformed or the displacement of the movable electrode is affected by the stress depending on the stress generated in the fixation section. In particular, in the case of a configuration in which the electric wiring to be connected to the fixation section is disposed in an under layer below the fixation section, and is made to have contact with the fixation section from the under layer, there is a problem that an upthrust stress caused in the contact section by the under layer cannot be fully absorbed by the stress-blocking slits.